arraylist副本 [英] arraylist copy
问题描述
我有以下代码：
Dim rNodeList As New ArrayList
Dim rNodeListNew作为新的ArrayList
对于iCntr As Integer = 0到tvRelations.Nodes.Count - 1
rNodeList.Add（tvRelations.Nodes（iCntr）.Text）
下一页
rNodeListNew = rNodeList
rNodeList.RemoveAt（2）
在我填充了rNodeList之后，它包含了8个元素。
rNodeListNew是这样的
但是当我删除rNodeList的元素2时，它也会被删除在
rNodeListNew。为什么？它们都指向相同的内存位置吗？
如何在vb中阻止它？
Thx
Hi,
I have the following code :
Dim rNodeList As New ArrayList
Dim rNodeListNew As New ArrayList
For iCntr As Integer = 0 To tvRelations.Nodes.Count - 1
rNodeList.Add(tvRelations.Nodes(iCntr).Text)
Next
rNodeListNew = rNodeList
rNodeList.RemoveAt(2)
after I''ve filled rNodeList, it contains 8 elements.
So does rNodeListNew
But when I remove the element 2 of rNodeList, it is also removed in
rNodeListNew. Why ? Do they both point to the same memory location ?
How can I prevent that in vb ?
Thx
推荐答案
2005年4月8日
将行rNodeListNew = rNodeList切换为：
rNodeList.CopyTo（rNodeListNew）
这应该将对象复制到新的arraylist中。这样，
arraylists不会指向相同的对象。如果你使用.Clone方法
那么两个arraylists仍将指向相同的对象。 HTH
Joseph MCAD
" Sam" < SA ************** @ voila.fr>在消息中写道
news：11 ********************** @ o13g2000cwo.googlegr oups.com ...
April 8, 2005
Switch the line rNodeListNew = rNodeList to:
rNodeList.CopyTo(rNodeListNew)
This should COPY the objects into the new arraylist. This way the
arraylists do not point to the same objects. If you use the .Clone method
then both arraylists will still point to the same objects. HTH
Joseph MCAD
"Sam" <sa**************@voila.fr> wrote in message
news:11**********************@o13g2000cwo.googlegr oups.com...
我有以下代码：
Dim rNodeList As New ArrayList
Dim rNodeListNew As New ArrayList
对于iCntr As Integer = 0到tvRelations.Nodes.Count - 1
rNodeList.Add（tvRelations.Nodes（iCntr）.Text）
下一页
rNodeListNew = rNodeList
rNodeList.RemoveAt（2）
在我填充rNodeList后，它包含8个元素。
rNodeListNew
但当我删除元素2对于rNodeList，它也在
rNodeListNew中删除。为什么？它们是否都指向相同的内存位置？
如何在vb中阻止它？
Thx
Hi,
I have the following code :
Dim rNodeList As New ArrayList
Dim rNodeListNew As New ArrayList
For iCntr As Integer = 0 To tvRelations.Nodes.Count - 1
rNodeList.Add(tvRelations.Nodes(iCntr).Text)
Next
rNodeListNew = rNodeList
rNodeList.RemoveAt(2)
after I''ve filled rNodeList, it contains 8 elements.
So does rNodeListNew
But when I remove the element 2 of rNodeList, it is also removed in
rNodeListNew. Why ? Do they both point to the same memory location ?
How can I prevent that in vb ?
Thx
尝试使用ArrayList的.Clone（）方法。
Marcie
2005年4月8日09:24:51 -0700，"山姆" < SA ************** @ voila.fr>写道：
Try the .Clone() method of the ArrayList.
Marcie
On 8 Apr 2005 09:24:51 -0700, "Sam" <sa**************@voila.fr> wrote:
我有以下代码：
Dim rNodeList As New ArrayList
Dim rNodeListNew As新的ArrayList
对于iCntr As Integer = 0到tvRelations.Nodes.Count - 1
rNodeList.Add（tvRelations.Nodes（iCntr）.Text）
下一页
rNodeListNew = rNodeList
rNodeList.RemoveAt（2）
在我填充rNodeList后，它包含8个元素。
rNodeListNew
<但是当我删除rNodeList的元素2时，它也会在
rNodeListNew中删除。为什么？它们是否都指向相同的内存位置？
如何在vb中阻止它？
Thx
Hi,
I have the following code :
Dim rNodeList As New ArrayList
Dim rNodeListNew As New ArrayList
For iCntr As Integer = 0 To tvRelations.Nodes.Count - 1
rNodeList.Add(tvRelations.Nodes(iCntr).Text)
Next
rNodeListNew = rNodeList
rNodeList.RemoveAt(2)
after I''ve filled rNodeList, it contains 8 elements.
So does rNodeListNew
But when I remove the element 2 of rNodeList, it is also removed in
rNodeListNew. Why ? Do they both point to the same memory location ?
How can I prevent that in vb ?
Thx
谢谢，那确实是克隆:)
thanks, that''s clone indeed :)
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